U.S. Pat. applications Ser. No. 608,616 filed Aug. 2, 1975 and Ser. No. 621,188 filed Oct. 9, 1975 show a roughing machine that includes a support for supporting bottom-up a shoe assembly that includes the margin of an upper. A roughing tool assembly, that includes a roughing tool, is located above the upper margin and is mounted for heightwise movement. Means are provided to so move the support as to move successive segments of the upper margin past the roughing tool. A yieldable force applying means is so connected to the roughing tool assembly as to yieldably urge the roughing tool downwardly against the upper margin to thereby enable the roughing tool to rough the upper margin segments.
The roughing tool is yieldably urged downwardly against the upper margin under relatively low pressure to prevent the roughing tool from penetrating too deeply into the upper margin and thereby unduly shred the upper margin. When a segment of the upper margin of higher elevation than its preceding segment, such as the ridge of a seam, is presented to the roughing tool, the roughing tool is caused to move upwardly against the yieldable pressure urging it downwardly. Because this pressure is relatively low, the roughing tool has a tendency to bounce upwardly of the upper margin and then settle down against the upper margin after a portion of the upper margin has passed the roughing tool, thus leaving an unroughed segment of the upper margin.